A wireless device such as a cellular telephone typically includes various components that communicate status, control and data information to each other. For example, a cellular telephone typically includes a transceiver that is adapted to transmit and receive at radio frequencies (RF). Cellular telephones further include a baseband processor that operates at baseband frequencies. Typically, information used to control the transceiver is provided from the baseband processor via analog signals on multiple pins, such as general purpose input/output (GPIO) pins. Additionally, baseband processors typically transmit radio data (e.g., voice information) to the transceiver via analog signals. Because there is a significant amount of information that is needed to be transferred, numerous such pins are needed, raising complexity, cost and consuming additional chip real estate.
For various reasons, digital interface communication protocols have been discussed in the communications industry, particularly with respect to cellular phones. One such effort has resulted in the DigRF Baseband/RF Digital Interface Specification currently available at the following URL on the Internet at the following URL—http://www.ttpcom.com/digrf. This specification defines certain logical, electrical and timing characteristics for a digital interface between an RF integrated circuit (RFIC), such as a transceiver, and a baseband processor. Part of this specification discusses a strobe signal that is sent by the baseband processor to the RFIC to precisely time events that will occur within the RFIC during transmit and/or receive sessions. Because the amount of event information being fed from the baseband processor to the RFIC can be considerable, the time required to send the event information to the RFIC can be large enough to interfere with the performance of the RFIC. The DigRF specification does not provide an efficient solution to this problem.
In addition to the amount of information sent, the fact that data and control information may now occur digitally raises concerns. Specifically, transmission of digital signals between a baseband processor and transceiver during the transceiver's transmit and receive sessions can cause undesired interference or other ill effects. Accordingly, a need exists to effectively use the availability of digital communication while avoiding such adverse effects.